The invention is in the field of processing of flat materials, in particular blanks and/or webs, of preferably textile materials, and relates to a method for gluing together such materials lying over one another. Furthermore the invention relates to devices for gluing together textile materials.
The gluing together of flat materials, in particular of material blanks and/or material webs is effected usually on so-called laminating machines using the application of heat and pressure. The flat materials to be glued together, lying over one another, between two belt faces facing one another of belt conveyors arranged over one another, are transported along heating elements. At the same time the belts of the belt conveyor, which are directed towards one another, with the flat materials lying therebetween slide along the heating elements. Usually behind a heating station provided with the heating elements there is arranged a cooling station with cooling elements which cool the materials heated up for gluing together.
If such pressure sensitive materials, for example so-called distance weavings are glued together, at the same time only a slight pressure may be exerted onto these materials. The gluing is effected then essentially only by way of the effect of heat. If such pressure-sensitive materials are to be glued together on laminating machines, then alone it is not sufficient to bring the heating and/or cooling elements allocated to the belt conveyors lying over one another to such a distance that the belt faces, directed towards one another, of the belt conveyors lying over one another have a distance corresponding to the total thickness of the materials to be glued together. Alone the weight which the sagging upper belt face of the upper belt conveyor exerts onto the upper side of the materials to be glued leads to a pressure loading which has a negative effect on pressure-sensitive materials. Such pressure-sensitive materials may be pressed so much together and thus compacted by the weight of the sagging upper belt face that in particular on account of the heat acting on the materials with the gluing, the compacting is irreversible, thus permanent.
Proceeding from this it is the object of the invention to provide a method and device with which also pressure-sensitive flat materials may be glued together without problem, in particular without permanent deformations (compacting).
In the method according to the invention for gluing together flat materials lying over one another, the materials between belt faces directed to one another of belt conveyors arranged over one another are led past heating elements and in particular also cooling elements. The belt face at least of an upper belt conyeyor, said belt face being allocated to the upper side of the materials, is held up without contact.
By way of the fact that at least the upper belt face, allocated to the upper side of the materials, of at least one upper belt conveyor (of the heating and/or cooling station) is held up without contact, a sagging of the upper belt face is alleviated. The weight force of the upper belt face may by way of this no longer rest on the flat materials to be glued together. By way of this a pressing-together of pressure-sensitive materials on gluing is effectively avoided, so that also no permanent deformations may arise.
According to a preferred further embodiment of the method the upper-lying upper belt face is not only held up without contact but also lifted up without contact. By way of this an initial sagging of the upper belt face is first alleviated and subsequently the upper belt face is held without sagging.
The contactless holding-up and where appropriate lifting of the upper belt face may be effected in a different manner. Preferably this is effected magnetically or pneumatically by way of a vacuum. It is also conceivable to hold up and where appropriate lift up the upper belt face magnetically as well as pneumatically. The lifting-up of the upper belt face may be effected magnetically as well as pneumatically, whilst the upper belt face is held up only magnetically or only pneumatically.
According to a preferred embodiment of the method the upper belt face is lifted up until below the heating elements and/or cooling elements. This is effected preferably in a manner such that the upper belt face bears below the lower side of the heating and/or cooling elements and here is held, and specifically without a gap, by which means there is guaranteed a good thermal conduction of the heating and cooling energy. The lower sides of the heating and/or cooling elements at the same time serve for the lift limitation on lifting up the upper belt face of the upper lying belt conveyor and define the course of the held-up upper belt face below the heating and/or cooling elements.
The device according to the invention for gluing together flat materials lying over one another comprises belt conveyors arranged over one another as well as heating and/or cooling elements. Between belt faces, facing one another, of the belt conveyor the materials are transportable past the heating and/or cooling elements. To the heating and cooling elements which are allocated to the belt face, facing the upper side of the materials, of the upper belt conveyor, there are allocated means for holding up the upper belt face.
Accordingly the (upper) belt face, of the upper-lying belt conveyor, which comes into contact with the upper side of the materials to be joined, is provided with means which hold up the upper belt face at least without contact. These means are in turn allocated to the heating and/or cooling elements, wherein they may be an integral part of the heating and/or cooling elements. It is however also conceivable alternatively or additionally to arrange the means neighboring the heating and/or cooling elements. In each case the means hold the upper belt face without contact on or below the heating and/or cooling elements. The means at the same time ensure a bearing of the upper belt face on the heating and/or cooling elements, by which means a good energy transmission to the upper transport belt and from there to the flat materials to be glued is ensured and simultaneously a sagging of the belt face of the belt conveyor concerned which loads the upper side of the flat materials is alleviated.
According to one possible embodiment of the invention the means are designed as suction air producers or suction means. With this it is preferably the case of suction bores, suction nozzles and/or narrow suction slots. In particular suction bores are provided which open in flat grooves on the lower sides of the heating and/or cooling elements. By way of this a contactless lifting up of the upper belt face over preferably the whole width is possible, by which means reliably and with low air or pressure losses a vacuum may be maintained for the reliable contactless holding-up of the upper belt face.
In one advantageous embodiment of the invention the suction bores or nozzles are connected to a vacuum channel. With this preferably the suction nozzles or likewise and the vacuum channels are integrated in the respective heating and/or cooling element. Usefully (but without this limiting the invention), to each heating and/or cooling element there is allocated an elongate groove as well as a suction air channel. The suction nozzles produce a vacuum in the respective groove in the base wallings of the heating and/or cooling elements allocated to the upper belt conveyor. By way of this the upper belt face is held over a large surface below the lower side of the upper cooling and/or heating elements that serves for the delivery of energy.
An alternative means for the contactless holding and where appropriate lifting of the upper belt face is formed by way of magnets, preferably permanent magnets. Above all permanent magnets have the advantage that they are self-sufficient, by which means the upper belt face may be held up without the expense of energy.
With the use of magnets at least the conveyor belt of each upper belt conveyor is designed such that it may be attracted by the magnets. For this in the conveyor belt there may be incorporated or interlaced metallic particles or metallic threads. In this manner the conveyor belt concerned may simply be made magnetically effective, wherein the conveyor belt otherwise must be formed of non-conductive and thus magnetically non-effective materials.
The magnets are preferably arranged outside the heating and/or cooling magnets, preferably between neighboring heating and/or cooling elements. This arrangement is made such that the lower sides of the magnets lie roughly in a plane formed by the base surfaces of the heating elements and/or cooling elements. Preferably the lower sides of the magnets are arranged slightly over the plane spanned by the base wallings of the heating and/or cooling elements. By way of this the magnets do not obtain a direct contact with the conveyor belt, which means always between the magnet and the conveyor belt there exists a thin air gap. By way of this it is ensured that the belt face, of the corresponding belt conveyor, which is allocated to the flat materials to be glued always bears below the heating and/or cooling elements. By way of this a favorable energy transition from the heating and/or cooling elements to the belt face of the conveyor belt is ensured, wherein the air gap between the belt face of the conveyor belt and the magnet acts in an insulating manner so that the energy delivered by the heating and/or cooling elements is effectively conducted to the flat materials to be glued and not to the magnets which by way of this in the region of the heating zone do not significantly heat up and on account of this could lose their effectiveness.
A further device according to the invention for gluing together flat materials lying over one another comprises belt conveyors arranged over one another, as well as heating and/or cooling elements. Between belt faces, facing one another, of the belt conveyor, the materials are transportable past the heating and/or cooling elements. The upper heating and/or cooling elements allocated to the or to each upper belt conveyor are movable up and down by way of a lift means.
Accordingly the heating and/or cooling elements, preferably the heating and/or cooling elements arranged over the flat materials to be glued together, may be moved up and down by way of a lifting means. By way of the lifting means the heating and/or cooling elements may be moved up and down simply and exactly in an infinite manner for setting and maintaining an exact gap or conveyor gap between belt faces, facing one another, of the conveyor belts of the belt conveyors arranged over one another for transporting through the flat materials to be glued together.
Preferably all heating elements of the heating zone which are arranged over the flat materials to be glued together are arranged on a frame and by way of this may be commonly moved up and down by the lifting means. Likewise a frame is allocated to all upper-lying cooling elements of the cooling zone so that also these may be commonly moved up and down by way of a (separate) lever drive allocated to them. The common adjusting of all heating elements on the one hand and all cooling elements on the other hand ensures a simple and uniform adaptation of all heating and/or cooling elements to the thicknesses of the sheet formation to be glued in each case.
To the frame for holding all heating elements on the one hand and all cooling elements on the other hand there are allocated guide members, preferably upright lift columns. By way of this a uniform and tilt-free up and down movement of the frames and thus all heating elements or cooling elements allocated to them is ensured. According to a preferred embodiment of the invention to each frame there are allocated four lift columns that preferably are allocated to the corners of the rectangular, square frame. In this case the lift means allocated to each frame comprises four toggle levers, wherein in each case one toggle lever serves for the up and downward movement of a lift column. The four toggle levers of the frame for all heating elements or of the frame for all cooling elements can preferably be actuated commonly, and specifically synchronously. By way of this all four guide columns for adjusting the heating elements or cooling elements are moved up and down uniformly and together, by which means all heating elements or cooling elements over their whole length are adjustable up and down uniformly by the same height amount.
For the synchronization of the toggle levers below the lift columns of the frame of the heating elements or of the cooling elements there serve push rods that in each case connect two toggle levers. Four toggle levers are then allocated to two push rods. These two push rods are in turn connected to one another so that all four toggle levers are mechanically coupled to one another and can be actuated to the same extent via a single drive, in particular a lift means such as for example a pressure means cylinder. It is also conceivable to mechanically connect to one another two toggle levers which are not connected to one another, by way of push rods by another coupling member, in particular a coupling rod, so that on actuation of one toggle lever the other toggle lever is co-moved. The coupling may also be effected hydraulically or pneumatically.
The described lifting means, in particular the drive of this ensures with a simple construction a reliable uniform up and down movement of all heating elements or cooling elements.